The World Health Organization (WHO) on Monday said that it has been working closely with experts from the United States, especially after the coronavirus outbreak, and all the information has been open to every country from the beginning.

Speaking at a virtual press conference from Geneva, WHO Director-General Tedros Adhanom Ghebreyesus said that his organization and the U.S. Centers for Disease Control and Prevention (CDC) have a long history of cooperation and "having CDC staff means there is nothing hidden from the U.S. from day one."

According to him, 15 members of the CDC staff had been working with the organization on COVID-19 response since January 1.

"There is no secret in WHO because keeping things confidential or secret is dangerous. There is no secret in WHO because it's about lives, and even a single life is very precious," Ghebreyesus stressed.

The administration of U.S. President Donald Trump was aware of real-time information on the novel coronavirus pandemic as early as the crisis unfolded, said a Washington Post report on Monday that appeared to contradict Trump's claim it was a failure of communication from the WHO that resulted in the spread of the virus in the U.S.

According to the report, a number of CDC staff members, including senior Trump-appointed health officials, were consulting regularly with the WHO as the crisis unfolded, U.S. and international officials were quoted as saying.

Read more:

Report: U.S. aware of real-time COVID-19 information from American officials at WHO

"We don't hide anything. We want all countries to get the same message immediately because that helps countries to prepare well and to prepare quickly," Tedros told reporters at Monday's press conference.

"We have been warning, we have been warning from day one. This is a devil that everybody should fight, we need strong national unity, we need global solidarity," the WHO chief stressed.

The WHO chief launched an impassioned appeal for nations around the world to come together to fight the COVID-19 pandemic instead of scoring political points with the pandemic.

"The cracks between people and parties are fueling it," said Ghebreyesus. "It's like playing with fire. It's the political problem that may fuel further this pandemic."

He called for strong national unity and global solidarity. "Without the two, trust us, the worst is yet ahead of us," he warned.

The WHO has placed orders for 30 million diagnostic tests over the next four months and was shipping nearly 180 million surgical masks in April and May. More than 600 hospitals were now ready to enroll patients in WHO's Solidarity Trial of drugs against the disease, he added.

(With input from Xinhua)